TIMBER BREAKAWAY GUARDRAIL POSTS
Tests are described which were designed to determine whether wood posts could adequately serve in breakaway (weak post) systems. There are 2 basic types of weak-post systems in current use. One utilizes a so- called strong beam, usually rectangular, welded steel tubing; the other uses a flexible railing, generally a standard steel W-rail (flex-beam) but ocassionally a steel-cable system. Data indicate that so long as the 1/4- inch bolt and the pipe insert are used, weak-wood posts could vary from 4- by 6-inch rough sawn, with no significant differences in system performance. These 2 are standard timber sizes. An alternate size is the 5 1/2 plus/minus 1/2 inch diameter, round wood post. Any of these three sizes will break under impact in the weak post system, where post spacing is 12.5 feet. Comments are also made regarding rail to post connection and railing height.
American Wood Preservers Institute1651 Old Meadow Road
McLean, VA United States 22101
- Publication Date: 1970-12
- Features: Appendices; Figures; Photos; References;
- Pagination: 6 p.
- TRT Terms: Breakaway supports; Guardrails; Performance; Posts; Steel rails; Testing; Timber construction; Wood structures
- Old TRIS Terms: Timber guardrails
- Subject Areas: Design; Geotechnology; Highways; Materials;
- Accession Number: 00153017
- Record Type: Publication
- Report/Paper Numbers: Report No. H3
- Files: TRIS
- Created Date: Jul 19 1977 12:00AM